During his stay in Italy in 1830-31, Felix Mendelssohn worked on two symphonies simultaneously. One was intended to capture the composer's current impressions of Italy, which he toured from Milan to Naples, the other to reflect on his journey to Scotland back in 1829. The Roman climate being hardly conducive to work on a Northern subject, it is no wonder that Mendelssohn finished the "Italian" Symphony first (he himself referred to it by that name). The "Scottish" Symphony was not completed until much later, in 1842.

The two symphonies seem to complement one another in several ways. Not only were they inspired by two completely different landscapes, some of their musical characteristics are also in contrast. The "Scottish" Symphony is in A minor with a last movement in A major, while the "Italian" Symphony is in A major with an A-minor finale (it is much more unusual to end a major-key symphony with a finale in the minor that the other way around).

Without an introduction, the first movement of the "Italian" Symphony begins with an exuberant melody bursting with youthful energy. A 19th-century commentator spoke about the "bright, sunny, laughing freshness" of the symphony, a quality established right at the very beginning. Other themes in the movement sing in parallel thirds, like a pair of lovers on an opera stage, or move about in light dance steps like the elves in A Midsummer Night's Dream.

The second-movement Andante con moto was probably inspired by a processional song Mendelssohn heard in Rome. It is occasionally dubbed "Pilgrim's March," because of a certain resemblance to the "Pilgrim's March" from Berlioz's Harold in Italy, another famous "Italian Symphony" from the 1830s. Another explanation wasproposed by musicologist Eric Werner, who traced the theme of the Andante to a song by Mendelssohn's teacher, Carl Friedrich Zelter. The text of the song ("There was a King in Thule") is from Goethe's Faust, in which Gretchen sings it as a ballad about a king in a distant land who has lost his beloved. Goethe was an important mentor to the young Mendelssohn, and since both he and Zelter died within a few months in 1832, it is possible that Mendelssohn intended this movement as a memorial to two men who had played important roles in his life.

The third movement (Con moto moderato) is really a minuet with Trio, although Mendelssohn didn't say so explicitly. The minuet section looks back to the days of Haydn and Mozart with a touch of nostalgia. The Trio, with its Romantic horn calls and puckish violin-and-flute theme, is more distinctly Mendelssohnian. After the recapitulation of the minuet, the Trio theme is hinted at once more, before the movement ends suddenly in a hushed pianissimo.

The Presto finale is titled Saltarello, after a quick folk dance of Southern Italy. Of its two main melodies, the first one is indeed a bouncing saltarello; the other, however, is a ceaselessly running tarantella (a different kind of Italian folk dance). Whether saltarello or tarantella, however, the dance character dominates the entire finale. It is only near the end that a more lyrical, slower-moving motif appears, but it is soon swept up in the returning dance rhythms.